A new encryption scheme for protecting 3G phone networks hasn't even gone into commercial use and already cryptographers have cracked it - at least theoretically.
In a paper published Tuesday, the cryptographers showed that the Kasumi cipher, which is also referred to as A5/3, can be broken using what's known as a related-key …

2^32 time

Algorithms

Well, for computer science studies of algorithms you've got in terms of program runtime O(n) (linear), O(n^2) O(n^3) (cubic time), O(log(n)) etc. For theoretical work you don't worry about n, if there's a n^3 algorithm for doing something you try to find a way to do it that's n^2 or n instead.. So iit takes 2^32 runs through an algoirthm that takes time n. Yeah, if the algorithm takes 1000 cycles it would run 1,000,000 times a second at 1ghz, "n" would be 1 microsecond... Faster CPUs would cut the time. Pipeline stalls and inefficiencies can drop a CPU well under 1 instruction per cycle, slowing things down. Optimizations could cut the run time a lot (both the compiler variety and "hand-optimized assembly" variety), conversely if the algorithm's really complex it could take well over 1000 cycles. So 0.1-50 microseconds or so would be my guesstimate on a likely range.

At 1 microsecond per run it'd take about an hour and 10 minutes. , it needs 64MB of data and 1GB of RAM.